python read the data from binary file and writing it to signed int

Question

im currently trying to get the bytes from python string and save it to signed int array i try to get all the bytes from the file than split the '\\x00' in an array then try to get the int from that byte but i keep getting the following error 'TypeError: cannot convert unicode object to bytes'

file=open('norm.raw','rb')
data=file.read()
file.close()
#data=binascii.b2a_hex(data)
byteArr=str(data)[2:-1]

for byte in byteArr:
    i+=1
    if byte == "\\":
        cadena.append(byteArr[j:j+i])
        j=j+i
        i=0
for stri in cadena:
    print(int.from_bytes('\\'+stri[:-1],byteorder='big',signed='true'))

dont know if this is the best way to get the signed int bytes from a file in python, if some one knows a better way to do it please help me.

edit: currently i can take the byte notation of a byte in the array i can extract the b'x02' but now i cant add the character \\ at the beginning to convert it to signed int.

Answer 1

There is a decode function that works on a bytes object.

bs = b'\x31'
x = int(bs.decode())

https://docs.python.org/3/library/stdtypes.html#bytes.decode

EDIT:

The previous version takes the unicode value to decode. If you have value stored in the raw byte. Then you can get integers in the following way.

binary_bytes = b'\xff\xf0\xff\xf0\xff\xf1\xff\xf0\xff\xf3\xff'

for i in range(len(binary_bytes)-1):
       print(int.from_bytes(binary_bytes[i:i+1], byteorder='big', signed='true'), end=', ')

Output : -1, -16, -1, -16, -1, -15, -1, -16, -1, -13, -1

Answer 2

This is an answer to your comment.

I suppose you have a range of bytes like this b'\\xff\\xf0\\xff\\xf0\\xff\\xf1\\xff\\xf0\\xff\\xf3\\xff'

So, you can do somthing like this in order to have your desired output:

def func(a):

    data = [a[k:k+1] for k in range(len(a))]
    final = []
    for k in data:
        final.append(int.from_bytes(k, byteorder = 'big', signed = True))

    return final

a = b'\xff\xf0\xff\xf0\xff\xf1\xff\xf0\xff\xf3\xff'

print(func(a))

Output:

[-1, -16, -1, -16, -1, -15, -1, -16, -1, -13, -1]